LYNN — When advocates for immigrants rallied to halt the deportation of Justo Barrios in June, they thought the case was a slam dunk. He came to America at age 16. The nuns at the convent on Green Street adore him. He plays Jesus in the church play.

Friends and supporters flooded federal immigration officials with letters and phone calls urging his release — all tactics that had worked in the past. But almost two months later, the 24-year-old construction worker from Lynn sat in Plymouth County jail fighting deportation to Guatemala.

Days after the Globe interviewed Barrios in custody, US immigration officers released him last Wednesday without explanation, but his case is among a string of deportation cases that have troubled advocates for immigrants and some US senators in recent weeks. Advocates say the Obama administration is still deporting immigrants who are not criminals or other top priorities, and who might soon apply for legal residency if Congress changes the law.